Apparatus for drying and the like



May 4,1926. 1,583,376

J. B. WELCH APPARATUS FOR DRYING AND THE LIKE Filed Dec. 5. 1924 2 Sheets-Sheet 1 INYENTOR 8. MA, w?

ATTORNEYS May 4,1925. i v 1,583,376

J. B. WELCH APPARATUS FOR DRYING AND THE LIKE Filed Dec. 5, 1924 2 Sheets-Sheet 2 INVENTOR B.

ATTORNEYS Patented May 4, 1926 JOHN IBERCHMANS WELCH, OF NEW ORLEANS, LOUISIANA.

APPARATUS FOR DRYING AND THE LIKE.

Application filed December To all whom it may concern:

Be it known that I, JOHN B. VVELCH, a citizen of the United States, residing at New Orleans, in the parish of Orleans, State of Louisiana, have invented certain new and useful Improvements in Apparatus for Drying and theilike; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in that art to which it appertains to make and, use the same.

This invention relates to apparatus for drying and the-like. Particularly, the invention relates to apparatus for drying materials, such as lumber, wood, or the like, re-

, tion.

The invention has for its object the provision of an improved apparatus of the character above described. More particularly, the invention aims to providean improved apparatus for treating materials requiring progressively different conditions of an operating medium as the material being treated undergoes characteristic changes in the course of the treatment operation, in which the condition of such operating medium is automaticallycontrolled in response to the characteristic changes in a representative sample of the material being treated so as to progressively establish and maintain the different conditions of such 0 crating mediumrequired in the course of t e treatment operation. As applled to dryin ap paratus, the invention aims to prov1 e an improved apparatus for drying materials, such as lumber or Wood, in which the temperature and/or humidity of the drying medium are automatically controlled in re sponse to changes in a varying characteristic (such as weight or moisture content) of the material being dried as the drying sprogresses. i

The improved apparatus of the invention is especially adapted for the dryin of lumher or wood, and on this account t e inven- 5, 1924. Serial No. 764,081.

tion will hereinafter be more particularly described as applied to that industry. It is to be understood, however, that the improved apparatus of the invention is applicable to the drying or treatment of other materials Where progressively different conditions of an operating medium are required as the material being treated undergoes characteristic 'plianges as a result of the treatment operaion. The improved apparatus of the invention 15 especially adapted for carrying out the method of dryin lumber, Wood, and the like, described an claimed in my copending application for Letters Patent of the United States filed May 24, 1924, Serial No. 715,516.

The controlling factors in the drying of lumber and of wood generally are the moisture content of the wood, the thickness of the Wood and the species. lVoods that are easily SUbJQClI to splitting in drying must be treated at low temperature and high humidity. If the wood has a high percentage of moisture the starting temperature must be lower and the humidity higher than if the same wood had been air-dried down to a low moisture -content before bein placed in the drying kiln. In other Wor s, the moisture content of the wood is the controlling factor for any particular thickness and species.

In the careful drying of wood, the moisture content of the Wood is first determined ar1 d the appropriate temperature and humidity of the drying medium for that moisture content are thereby established. After the wood has been dried down to a lower moisture content more severe conditions of temperature and humidity of the drying medium are allowable. Heretofore, in the carein] drying of wood, it has been necessary for the operator to periodicall go into the kiln, take a sample of the woo undergoing drymg and make av moisture determination of that sample in order to find out ifthe mois-' ture content is low enough to permit or warrant a, new setting of the conditions of temperature and humidity. In practice, this necessitates daily weighing of samples from eaclrkiln to determine the appropriate conditions for the drying o erations. Often, even in the hands of a skillful operator, the dryingcproceeds too far before conditions are change and then again conditions are some times changed before the lumber or wood is dry enough to stand the altered conditions of temperature and humidity.

The hi h temperatures and humidity with in a lum er drying kiln make the duty of entering the kiln for obtaining samples most arduous and on this account the drying is seldom controlled by the moisture content of the wood as it should be but is more often based on a time schedule. This schedule is set after the moisture content of the woods is determined and before drying commences. If everything proceeds without interruption, good drying may be accomplished. However, any interruptions in the drying, such as low steam ressure, shutting down of the kilns or boi ers for repairs, changes in weather conditions which affect the temperature within the kiln, and a variety of other causes often slow up the actual drying so that the lumber or wood is not able to stand the increasing temperature and decreasing humidity called for by the drying time schedule. As a result, there is often a considerable loss of lumber due to splitting caused by too rapid drying.

In the improved apparatus of the present invention, a representative sample of the material being treated automatically prescribes the appropriate difierent conditions of the operating medium required in the course of the treatment operation. Thus, the improved apparatus of the invention includes appropriate controlling instrumentalities for establishing and maintaining different desired conditions of the operating medium, such, for example, as different conditions of temperature and/or humidity with in a lumber drying kiln. In the apparatus of' the invention the controlling instrumentalities are automatically set or adjusted by control means responsive to characteristic changes (such as changes in weight or moisture content) in a representative sample of the material being treated. Thus, the control means produces an action indicative of the characteristic changes in the representative sample as the treatment operation progresses, and this action is caused to so ad]ust the controlling instrumentalities as to establish and maintain the different conditions of the operating medium required inthe course of the treatment operation. Preferably, the controlling instrumentalities are actuated by a movable cam of such configuration or deropriately moved, the cam progressively a justs or sets the control instrumentalities to maintain predetermined different conditions of the operating medium (for example, predetermined different conditions of temperature and/or humidity within a lumber drying kiln). Any appropriate mechanism may be employed for operatively connecting the control means to the controlling instrumentalities. In what I now consider the preferred form of the invention, this mechanism is of the electromagnetic type periodically ener ized or operated by the engagement of a fiovable contact member (responsive to characteristic changes in the representative sample) with ap ropriately spaced electric contacts.

3 embodied in an apparatus for drying materials such as lumber or wood, the apparatus of the invention includes a temperature and/or humidity controller or controllers having temperature-setting means .(and/ or humidity-setting means) cooperating with means for maintaining the temperature substantially uniform (and/or means for maintaining the humidity substantially uniform),

in combination with a suitable mechanism (preferably an electromagnetic device) for adjusting the tem erature-setting means (and/or the humi ity-setting means) to maintain the different conditions of temperature (and/or humidity) required in the course of the dryin operation, such mechanism being controlled by an action indicative of the loss (or change) in weight of a representative sample of the material being dried-as the drying operation progresses. The temperature and humidity controllers may be of well-known types and may be conveniently modified for inclusion in the improved apparatus of the invention by the provision of cams of appropriate confi uration or design for effecting the desire settings or adjustments of the controllers. The cams are opcratively connected to the control means responsive to changes in weight of the representative sample of the material being dried.

- The novel features of the invention will be more clearly understood from the follow-"' ing description taken in conjunction with the accompanving drawings, in whieh Fig. 1 diagrammatically illustrates What I now consider the preferred embodiment of the invention, and

Fig. 2 illustrates a modified contact-makingrdevice.

1g. 3 shows a detail view of the contactmaking device of Fig. 2.

The apparatus illustrated in Fig. 1 of the drawings is particularly adapted for controll ng the conditions of temperature and humidity within a, lumber dryln kiln, and is shown in the drawings as applied to that purpose. The kiln is provided with heating pipes adapted to be supplied with steam from a steam main 5. A com ressed air operated valve 6 is included in t e steam main 5 and is adapted to be manipulated by the automatic temperature controlling instrurnentalities hereinafter described. The kiln is further provided with a spray system 7 in the supply pipe of which is positioned a compressed air-operated valve 8. The kiln is further provided with a damper 9 arranged to be manipulated by the compressed air-operated valve 10. The spray valve 8 and damper valve 10 are actuated by the automatic humidity controlling instrumentalities hereinafter described. l

A representative sample 11 of'the lumber- (or other material) to be dried is appropriate] associated with a special type of scales or 'alancing device opcratively mounted throughout the kiln In the drying of lumher, the sample 11 may conveniently be approximately 8 incheswide, 24 inches long therewith.

and the average thickness of the lumber undergoing drying.

The sample 11 is carried by a pair of depending grab hooks 12 pivotally mounted near one endof a horizontally positioned balance arm 13. The balance arm is operatively supported by a pair of knife-edge ivots 14, one on each side of the arm. A

alancing wei ht 15 is mounted on the arm 13, the balanci g weight 15 and grab hooks 12 being positioned on opposite sides of the pivots 14. The balancing weight 15 is designed to counterbalance the grab hooksv 12 and when appropriatelyy adjusted brings the balance arm 13 toa alanced position when. no sample is carried by the grab hooks.

A flexible stra- 16 is secured to the underside of the ba ance arm 13, between the pivot 14 and the adjustable weight 15, and has its other end secured to an appropriately pivoted drum 17. A depending arm 8 is secured to the pivoted drum 17 and moves An adjustable weight. 19 is mounted on the arm 18. The arm 18 has a scale 20 for indicating the position thereon of the adjustable weight 19.

A link 21 connects the pivoted drum 17 with a pivoted sector-shaped gear 22 meshing with a pinion 23; A combined electric contact and pointer 24 is.secured.to the pinion 23 and is adapted to sweep over and alternately engagetwo series of stationary a electric contacts 25 and 26. By means of the gears 22 and 23 a small movement of the pivoted drum 17 is translated into a. greater movement of the-contact pointer 24p A scale or dial 24' is associated with the pointer 24 and is graduated in percentage moisturefrom 0 to 200 per cent.

The inovableoontact pointer '24 is, elec trically connected". by afconduotor 2710a terminal or binding post. 28 and thenceby aconduc'tor 29 to one contact pf a switch 30; The stationary contacts 25 are electrically connected together and to a. terminal or binding post 31. The'co'ntacts 26 are similarly connected together and to a binding post A conductor 33-connects thebinding post 31 to astationar'y contact. 34, and

similarly the terminal 32 is connected bya conductor 35 to a stationary contact 36'.

The switch 30 is connected through a battery 37, or other appropriate source of elec* tric energy to one terminal of a constant speed electric motor 38, theother terminal of the motor being grounded at 39.

The shaft of the motor 38 carriesa' worm 40 meshing with a gear 41. A pinion 442 is secured to the gear 41 and meshes witha gear 43 to which is secured-a movable contact 44. The movable contact 44 rotates with the gear 43 and. has afsubstantially semi-circular contact element of such configuration that it is alwaysiinfiengagement with either one or the other-of the contacts 34 and 36 and in two positions of eaichrevolution engages both ot'thel contacts 3.4

and 36. a V t The contact 44 carries two'diametrically bined and mounted-in a singleinstrument 95 case indicated generally by, reference char acter 48 in the drawings. y Y

A cam lever za'rm 49 is associated withthe cam 47 and is operatively connected .to a

temperaturesetting means or pointer50. It

will be understoodthat movement of the lever 49 is a-p 'rop'ri'ate'ly transmittedto the pointer 50... imilarly, a humidity-setting means or pointer 51 is 'operatively con? nected to and adapted. to be'actuated 'by.the 5' humidity-adjustingcam secured to thestar wheel 46, but notshown-in theaccompany ing drawin'gsyfor the sake of simplicity.

A duplex valve mechanism is mounted within the casev 48 of'the. combined term 110 perature' and humiditycontroller illustrated 1n the accompanying drawings, ThIS mechanlsm comprises. a, temperature control;

valve having a valve chamber 52 which com} mumcates by a passage 53 with a compressed air supply pipe 54. The valve chamber 52 contains a valve-head 55 adapted to. Open or close a port 56 to the. atmosphere andf simultaneously to 'close or open (respectively) the"passage 53. The valve head. 55 120' is carried by a hollow valve stem 57 proi .vidzin communication between the "valve' chamherz52 and a bellows diaphragm 58. The diaphragm" 58 communicates bye-"flex ible tubing 59 with an air nozzle 60- mounted upon the temp'eraturesetting pointer 50. "A

, flapper valve 61- is mounted upon atempe'ra- ,ture-indicating pointer 62 so as to close the air nozzle 60as the temperature-indicating pointer 62 moves into a predetermined posipositionedpins 45 adapted (inconsequence tion with respect to the temperature-setting pointer 50. An air pipe 63. provides com-- muuication between the valve chamber 52 and the air operated steam valve 6.

The humidity control valve is of similar construction to the temperature control valve and comprisesa valve chamber 64 having a passage connected to the air supply pipe 54. A valve head 66 is adapted to open or close a port 67 to the atmosphere and simultaneously to close or open (respectively) the passage 65. The valve head (36 is mounted on a hollow valve stem 68 communicating between the valve chamber 64 and a bellows diaphragm (39. The diaphragm (i9 communicates by a flexible tubing with an air nozzle 71 mounted on the humidity-setting pointer 51. A flapper valve 72 is mounted on a humidity-indicating pointer 7 3 to close the air nozzle 71 as the humidity-indicating pointer 51 approaches within a predeter-- mined distance of the humidity-setting pointer 73. An air pipe '74 communicates between the valve chamber 64 and the air operated spray valve 8. The air pipe 74 also communicates with the damper valve 10 for opening or closing the damper 9.

The air pipes 54, 63 and 74 are provided with pressure gauges to. indicate the air pressure in these lines.

The temperature-indicating pointer 62 is actuated by a temperature element or dry bulb 76, while the humidity-indicating pointer 73 is actuated by a wet bulb 7 7 The temperature element or dry bulb 7 6 is of the usual type, containing a volatile liquid which, when subjected to heat, volatilizes and the resulting vapor pressure is transmitted throu h a flexible tube 7 8 to a helical coil 79. he movement of the helical coil 79 is transmitted to the temperature-hulleating pointer 62 by means of links and 81. The humidity-indicating pointer 73 is actuated in like manner by the wet bulb 77 through the flexible tube 82, helical coil 83 and links 84 and,85.

The operation of the apparatus is substantially as follows. The initial moisture content in per cent of the representative sample 11 is first determined. This may conveniently be done by theautocalculator, a device for directly measuring or indicating the moisture content of a sample of lumber. sample is then secured to therab hooks 12, and the weight 19 adjuste until the pointer 24 indicates on the scale 24 the determined initial moisture content of the sample 11. Thereafter (as the moisture content of the sample decreases in the course of the drying operation) the position of the pointer 24 with respect to the scale 24 will directly indicate the actual percentage moisture content of the sample 11. The apparatus is then ready to proceed with the control of the drying.

The

( As the moisture content in the sample 11 decreases, in the progress of the drying operation, the contact pointer 24 engages first a contact 25 and then a contact 26, and so on alternately engaging a contact 25 and a contact 26 throughout the drying operation. When the pointer 24 engages a contact 25 the contact element 44 will be in engagement with the contact 34 and the electric motor 38 will be energized through the circuit 3l-383444-groundmotor-3730- 292827-2425. The motor will thereupon operate to turn the gear 43 and contact 44 through one half revolution, when the contact 44 will move out of engagement with the contact 34, but not until the contact 44 has moved into engagement with the contact 36. As the drying progresses, the pointer 24 moves from engagement with one of the contacts 25 into engagement with the next adjacent contact 26, whereupon the electric motor is again energized and the gear 43 and contact 44 moved half a revolution. This sequence of operations is repeatedthroughout the entire drying operatlon.

Each time the electric motor 38 is energized, one of the pins 45 engages in a teeth of the star wheel 46 and turns the star wheel through a predetermined angle. This movement of the star wheel is transmitted to the temperature-adjusting cam 47 and to the humidity-adjusting cam (not shown). In this manner, the temperature-setting pointer 50 is moved a predetermined prescribed amount by means of its operative connection with the cam lever 49 each time the electric motor 38 is energized. Likewise, the humidity-setting pointer 51 is moved a predetermined prescribed amount each time the motor is energized. t

The star wheel 46 is moved uniformly, that is, through the same angle, each time the motor 38 is energized. The temperature adjusting cam 47 is designed to progressively move the temperature-setting pointer 50 so as to maintain within the kiln a desired drying schedule with respect to temperature throughout the entire drying operation. Different drying schedules may be obtained, as required, by employing temperatureadjusting cams 47 of the appropriate different configuration or design.

When the valve head 55 closes the port 56 and opens the passage 53, the air supply pipe 54 is in direct communication with the air pipe 63, thereby permitting compressed kiln rises (due to the open steam valve 6),

6 thereupon closes and 1: shuts off the steam supply to the kiln. When the temperature within the kiln has again fallen to below the predetermined prescribed temperature, the temperature-indicating pointer 62 will move away from the temperature-setting pointer 50, causing disengagement between the nozzle 60 and the flapper valve 61. The bellows diaphragm 58 -will then contract and permit the valve head 55 to return to its original position, whereupon the steam valve 6 is again opened by the action of the compressed air in the pipe 63.

In a similar manner, when the humidity within the kiln falls below the predetermined prescribed condition, the humidityindicating pointer 73 will move towards the humidity-setting pointer 51 until the flapper valve 72 closes the air nozzle 71. This causes the escape ofthe compressed air in the pipe 73 and the attendant appropriate manipulation of the spray valve 8 and damper valve 10 for increasing the humidity within the kiln. i

As the .drying operation pro resses, the moisture content of the material eing dried becomes lower and more severe conditions of temperature and humidity become possible. The loss in weight of the representative sample 11 sets in action the controlling instrumentalities that establish and maintain these different and more severe conditions of temperature and humidity. As hereinbefore mentioned, any appropriate or desired schedule of temperature and humidity conditions may be established and maintained-within the kiln by employing a temperature-adjusting cam (47) and a humidity-adjusting cam of the pro-per designs.

In'the apparatus illustrated i" the drawings, the temperature-settingpointer 50 is adjustably connected to the cam shaft 49 so that the cam schedule may, if desired, be

adjusted to read higher or lower over the whole course of the cams action. Thus, the pointer 50 is rigidly secured to an arm 86. Thearm 86 is adjustably' connected tothe cam arm 49 by a threaded rod 8?. The rod 87 engages sorew-threaded elements secured to the arms 49 and 86 in such a manner that by turning the r021 87 the relative o'eitions' e the cam arm 49 and ointer t are up .tact 99 is connected \vit propriatel adjusted. A s rin '88 is secured to t e arm 86and ho ds t 'e cam follower of the arm 49 against the cam 47.

It will have been understood from the foregoin description that the movable contact 44 1s electrically grounded, as at 90. The contacting element of the stationary contacts 34-and 36 is preferably a pair of resilient, spaced contacts between which the contacting element of the movable contact 44 passes, as. in the well-known knife switches.

The apparatus illustrated in the drawings provides a positive motor action for adjusting the humidity-setting means and the temperature-setting means. This motor action is definitely controlled by a positive, but simple, switch movement. The apparatus has no parts that are likely to become stuck in operation and no electrical windings that are likely to become overheated and burned out.

appropriate scale may, if desired, be associated with the star wheel 46 whereby the moisture content of the'representative sample can be directly read at any time durmg the drying operation. This is possible because the movement of the start wheel 46 is directly proportional to the loss in moisture of the representative sample. By this means the moisture content of the material being dried can be accurately indicated wherever the controlling instruments are located which may, of course, be remote from the kiln itself.

In Fig. 2 of the drawings, I have illustrated a modified contact-making device. This device may be employed in place of the alternate contacts 25 and 26 illustrated in Fig. 1. The same parts in Fi 1 and 2 are iiidicated by the same re crence characters. As shown in Fig. 2, a cam 91 is secured to the shaft u on which is positioned the pinion 23 so t at with each movement of the scalebeam 13 and the pinion 23 there will be a corresponding movement of the cam 91. The cam 91, if desired, may have positioned thereon a scale calibrated in terms of percentage moisture content and the percentage moisture content of the material undergoing treatment may then be indicated by a stationary marker 92. The mercury contact-making device is secured to a frame 95 suspended from apivot 93 and is adapted to betilted by a cam follower 94 secured to the frame 95. The mercury contact-making device comprises a sealed glass tube 96 containing a small amount of mercury 97. Electric contacts 98 and 99 ierce/each end, respectively, of the sealed g ass tube 96 and are appropriately associated with a common contact- 100 so that either contact 98 or conthe common con tact 100 by the me any 97 whetrthe' con tact device in rtia; one way or the other Contacts 98, 99 and 100 are connected to the binding posts 31, 32 and 28, respectively, by conductors 101, 102 and 103.

As the moisture content of the sample 11 decreases the cam 91. turns and raises or lowers the cam follower 95 to tilt the mercury contact-making device one way or the other, thereby causing the mercury 97 to alternately close the circuits through the motor 38 by connecting first contacts 98 and 100 and then contacts 99 and 100.

Vhile I have described and illustrated an apparatus embodying a combined temperature and humidity controller in a single casing or instrument. it will be readily understood by those skilled in the art that the principles of the invention are equally applicable to an apparatus embodying a tem perature controller alone or a humidity controller alone, or an independent temperature controller and an independent humidity controller. y

Ordinarily, the control means will be located within the kiln, while the controlling instruinentalities will be conveniently located without the kiln. If desired, however, the control sample (11) may be suspended by a wire through an appropriate opening in the roof of the kiln and all other parts of the apparatus located outside the kiln. In any event, the change or loss in Weight of the control sample (11) as the drying progresses, produces an action (movement of the contact-pointer 24, Fig. 1, or cam 91, Fig. 2) indicative of this change in weight, aud that action automatically controls the setting of the temperature and/or humidity controllers so as to progressively establish and maintain the predetermined different conditions of temperature and/or humidity within the kiln called for by the drying schedule.

While the embodiment of the invention herein described and illustrated is especially suited for the drying of lumber or wood, it will be understood by those skilled in the art that this particular embodiment of the invention is equally welladapted for use. in the drying of other materials requiring different conditions of temperature and/or humidity in the course of the drying operation. Furthermore, the principles of the invention are applicable to many industries and uses where different conditions of one or more operating media are required in the course of a treatment operation, Thus, in many manufacturing processes, different conditions of one or more operating media are necessary as certain characteristic changes are encountered and the apparatus of the invention may be advantageously be employed to automatically establish and maintain such different operating conditions in response to such characteristic changes.

I have explained my invention by illustrating and describing a certain specific embodimen't thereof, but various modifications of the details of construction and arrangement of parts in this embodiment of the invention will present themselves to those skilled in the art. I, accordingly, do not wish to be restricted to the articular form or construction disclosed lierein by way of example for the'purpose of settin forth my invention in accordance with tile patent statutes. The terms of the appended claims are, therefore, not restricted to the precise structure disclosed, but are intended to cover all changes and modifications within the spirit and scope of the, invention.

I claim:

1. In an apparatus for the treatment of materials reguiring progressively difierent conditions 0 an operating medium as the material being treated undergoes characteristic changes in the course of the treatment operation, the combination of controlling instrumentalities adapted to be adjusted so as to establish and maintain different conditions of said operating medium, control means responsive to said characteristic changes in a representative sample of the material being treated, and means actuated by said control means for adjusting said controlling instrumentalities to progressively establish and maintain the difierent conditions of said operating medium required in the course of the treatment operation.

2. In an apparatus for the treatment of materials requiring progressively different conditions of an operating medium as the material being treated undergoes characteristic changes in the course of the treatment operation, the combination of'controllin instrumentalities adapted to be adjuste so as to establish and maintain different conditions of said operating medium, movable means operatively associated with said instrumentalities and adapted when appropriately moved to adjust said instrumentalities to establish and maintain predetermined different conditions of said operating medium, control means responsive to said characteristic chan es in a representative sample of the material being treated, and means actuated by said control means and operatively connected to said movable means for adjusting said controlling instrumentalities to progressively establish and maintain the different conditions of said operating medium required in the course of the treatment operation.

In an apparatus for the treatment of materials requiring progressively different conditions of an operating medium as the material being treated undergoes character istic changes in the course of the treatment operation, the combination of controlling instrumentalities adapted to be adjusted so as to establish and maintain difl'erent conditions of said operating medium, control *ditions of said operating medium, cent 01 ferent conditions of said 0- erating medium required in the course of t eration. c

4; In an apparatus forthe treatment of materials requiring progressively difierent conditions of an operatin medium as the material bein treated un er oes charactere treatment opistic changes 1n. the course 0 the treatment.

operation, the combination of controlling instrumentalities adapted to be adjusted so as to establish and maintain different conmeans responsive to 'said: characteris ic changes in a representative sample of the material being treated, said control means including two series of alternately arranged spaced electric contacts and a cooperating movable contact member adapted to progressively engage said spaced contacts in consequence 0 said characteristic changes in said .representativesample as the treatment operation progresses, each of said series of spaced electric contacts being included in a different electric circuit, an electromotive device arrangedto be included in each of said circuits, means whereby said circuits are alternately completed and said electromotiye device energized and operated by the progressive engagement of said movable contact member with said spaced contacts and means whereby the operation of said electromotive device adjust saidi controlling instrumentalitiesto rogressively establish and maintain the sifi'erent conditions of said operating medium required in the course of the treatment operation.

5. In an apparatus for the treatment of 'materials requiring progressively difi'erent conditions of an operatin medium as the material being treated-un er oes characteristic changes in the course 0 he treatment operation, t e combination of controlling instrumentalit es adapted to be adjusted so as to establish and maintain difierent conditions of said 0 crating medium, movable means operati? yassociated with said instrumentalitie and adapted when appropriately moved to adjust said instrumentalities to establish a d maintain predetermined different conditi ns of said operatin g medium, control means responsive to said characteriistic changes in a representative sample of the ma erial being treated, said control means including a series of spaced electric contacts and a cooperating movable contact member arranged to progressively en- 7 gage said spaced contacts in consequence of said characteristic changesin said rep rcsentative sample as 'thetreatment operation progresses, and electromagnetic means actuated by the engagement of said movable contact member with said spaced contacts and'operatively connected to said movable means for ad uBting' said controlling instrumentalities to progressively establish and maintain the different conditions of said operating 'medium required in the course of the treatment operation. l I 6. Inan apparatus for the treatment oi" materials requiring progressively difl'erent conditions of an operating medium' as the" 35 treated under oes charactem material being istic changes in the courseo the treatment operation, the combination of controllin in strumentalities adapted to be adjust'e so as to establish and maintain difl'erent' conditions of said operating medium, 'movable means operative y associated with said instrumentalities and adapted when appropriately moved to adjust said instrumentalities to establish and maintain predetermined diii'erent conditions of said operating medium, control means responsive to said-characteristic changes in a representative sample of the material being treated,

said control means including two series of alternately arranged spaced electric contacts anda cooperating movable contact member adapted to progressively engage said spaced contacts in consequence of said characteristic changes in'said represenative sample as the treatment operation progresses, each of said series of spaced electric contacts being in eluded in a different electric circuit, an elec-' tromotive device arranged to be included in each of said circuits, means whereby said circuits are alternately completed and said electromotive device energized andoperated by the progressive engagement of said movable contact member with said spaced contacts, and means whereby the operation of said electromotive device moves said movable means and thereby adjusts said controlling instrumentalities to progressively establish and maintain the different conditions of said operating medium required in the course of the treatment operation.

7. In an apparatus for the treatment of materials requiring progressii'ely different conditions of'an operating medium as the material under treatment changes inweight in the courseo'fthe treatment operation, the a combination of controlling instrumentalities adapted to be adjusted so as to establish and maintain different conditions of sard opcrating medium, control means-responsive til to changes in weight of a representative sample of the material undergo ng treatment, and means actuated by said control means for adjusting said controlling 1nstrumentalities to progressively establish and maintain the different conditions of said operating medium required in the course or the treatment operation.

8. In an apparatus for the treatment of materials requiring progressively dili'ercnt conditions of an operating medium as the material under treatment changes in weight in the course of the treatment operation, the combination of controlling instrumentalities adapted to be adjusted so as to establish and maintain ditl'crent conditions of sa1d oper ating medium, control means responsive to changes in weight of a representative sample of the material undergoing treatment. said control means including a ser1es o spaced electric contacts and a cooperating movable contact member operatively connected to a balancing device and arranged to progressively engage said spaced contacts in consequence of the change in weight of said representative sample as the treatment operation progresses, and electromagnetic means actuated by the engagement of said movable contact member with said spaced contacts for adjusting said controlling instrumentalities to progressively establish and maintain the ditferent conditions of said operating medium required in the course of the treatinent operation.

9. In an apparatus for the treatment of materials requiring progressively different conditions of an operating medium as the material under treatment changes in Weight in the course of the treatment operatiomthe combination of controlling instrumentalities adapted to be adjusted so as to establish and maintain different conditions of said operating medium, movable means operative y associated with said instrumentalities and adapted when appropriately moved to adjust said instrumentalities to establish and maintain predetermined different conditions of said operating medium, control means responsive to changes in weight of a representative sample of the material undergoing treatment, and means actuated by said control means and operatively connected to said movable means for adjusting said controlling instrumcntalities to progressively establish and maintain the different conditions of said operating medium required in'thc course of the treatment operation.

10. In an apparatus for the treatment of materials requiring progressively different conditions of an operating medium as the material under treatment changes in weight in the course of the treatment operation, the combination of controlling instrumentalities adapted to be adjusted so as to establish and maintain difierent conditions of said oper- Lssaeve ating medium, movable means 0 eratively associated with said instrumenta ities and adapted when appro riately moved to adjust said instrumenta ities to establish and maintain predetermined different conditions of said operating medium, control means responsive to chan es'in weight of a representative sample 0? the material undergoing treatment, said control means including a series of spaced electric contacts and a cooperating movable contact member operatively connected to a balancing device and arranged to progressively engage said spaced contacts in consequence of the change in weight of said representative sample as the treatment operation pro esses, and electromagnetic means actuate by the engagement of said movable contact member with said spaced contacts and operatively connected to said movable means for adjusting said controlling instrumentalities to rogressively establish and maintain the dilgerent conditions of said operating medium required in the courseof the treatment operation.

11. In an apparatus for the treatment of materials re uiring progressively different conditions 0 an operatin medium as the material under treatment c anges in Weight in the course of the treatment operation, the combination of controlling instrumentalities adapted to be adjusted so as to establish and maintain difierent conditions of said operating medium, control means responsive to changes in weight of a representative sample of the material undergoing treatment, said control means including two series of alternatively arranged spaced electric contacts and a cooperating movable contact member operatively connected to a. balancing device and arranged to progressively engage said spaced contacts in consequence of the change in weight of said representative sample as the treatment operation progresses, each of said series of spaced electric contacts being included in a different electric circuit, an electromotive device arranged to be included in each of said circuits, means whereby said circuits are alternately completed and said electromotive device energized and operated by the progressive engagement of said movable contact member with said spaced contacts, and means whereby the operation of said electromotive device adjusts said controlling instrumentalities to progressively establish and maintain the differentconditions of said operating medium repaired in the course of the treatment operaion.

12. In an apparatus for the treatment of materials requiring progressively different conditions of an operating medium as the material under treatment changes in weight in the course of the treatment operation, the combination of controlling instrumentalities adapted to be adjusted was to establish and maintain difierent conditions of said operating medium, movable-fmeans operatively associated with said instrumentalities and adapted when appropriately moved to adjust said instrumentalities to establish and maintain predetermined different conditions of said operating medium, control means responsive to chan es in weight of a representative sample 0? the material undergoing treatment, said control means including two series of alternately arranged spaced electric contacts and a cooperating movable contact member operatively connected to a balancing device and arranged to progressively engage said spaced contacts in consequence of the change in weight of said representative sample as the treatment operation progresses, each of said series of spaced electric contacts being included in a difi'erentelectric circuit, an electromotive device arranged to be included in each of said conduits, means whereby said circuits are alternately completed and said electromotive device energized and operated b the progressive engagement of said mova le contact member with said spaced contacts, and means whereby the operation of said electromotive device moves said movable means and thereby adjusts said controllin instrumentalities to progressively establis and maintain the different con-- ditions of said operating medium required in the course of the treatment 0 eration.

13. In a drying apparatus 0 the character described provided with means for controlling the temperature and humidity conditions therein, means for producing an action indicative of changes in a varying characteristic of a representative sample of the material being dried as the drying operation progresses, and means operatively controlled by said action for establishing the conditions of temperature and humidity to be maintained within the apparatus by said temperature and humidity controlling means.

14. In a drying apparatus of the character described provided with means for controlling the temperature and humidity conditions therein, means for producing an ac tion indicative of the loss in weight of a representative sample of the material being dried as the drying operation progresses, and means 0 eratively controlled by said action for esta lishing'the conditions of temperature and humidity to be maintained within the apparatus by said temperature and humidity controlling means.

15. In a drying apparatus of the character described provided with means for con trolling the temperature and humidity conditions therein, means for producing within the kiln a continuous action indicative of the loss in weight of a representative sample of the material being dried as the drying op; eration progresses, and means operatively dium of the apparatus, means for controlled by said action for temperature means.

16. An apparatus for dr'ing materials which require dilterent con itions of temperature and humidity during the drying operation, comprising means for varying the temperature and humidity of the drying mereducing within the apparatus an action in icative of changes in a varying characteristic of a representative sample of the material being dried as the drying operation progresses, and means operatively controlled by said action and operatively associated with said temperature and humidity varying means for establishing and maintaining predetermined diilerent conditions of temperature and humidity of the drying medium of the apparatus as the drying operation progresses.

17. An apparatus for drying materials which require different conditions of temperature and humidity during the drying operation, comprising means for varying the temperature and humidity of the drying medium of the apparatus, means tor producing within the apparatus a continuing action indicative of the loss in weight of a representative sample of the material being dried as the drying operation progresses, and means operatively controlled eratively associated with said temperature and humidity varying means fornestablishing and maintaining predetermined difi'erent conditions of temperature and humidity of the drying medium of the apparatus as the drying operation progresses.

18. An apparatus for dr 'ing materials which require different con itions of temperature and humidity during the drying operation, comprising means for varying the temperature within said apparatus, means for varying the humidity within said apparatus, means for producing within the apparatus a continuing action indicative of the loss in weight of a representative sample of the material being dried as the drying operation progresses, temperature res onsive means within said apparatus, humi ity responsive means within said apparatus, means cooperatin with said temperature varyingmeans and said temperature responsive means for maintaining the temperature within said apparatus substantially uniform.

and' humidity controlling 'means cooperating with said humidity varying means and said humidity responsive means for maintaining the humidity within said apparatus substantially uniform, and means operatively controlled by said action and operatively associated with said last two mentioned means for adjusting theconditions of temperature and humidity to be maintained substantially uniform thereby.

19. The combination in a drying apparaadjusting said by said action and optus having temperature varying means and humidity varying means and controllers cooperating therewith for maintaining any J desired conditions of temperature and hutemperature, and humidity within the drying apparatus as the drying operation progresses. t

20. The combination in a drying apparatus having temperature varying means and a controller cooperating therewith for maintaining any desired condition of temperature within the apparatus, of control means "movable in response to the loss in weight of a representative sample of thematerial beried as the drying operation progresses, an electromagnetic device arranged to be actuated by said control means, and means operated by said electromagnetic device for justing said controller to maintain predetermined different conditions of temperature within the drying apparatus as the drying operation progresses.

21. The combination in a drying apparatus having humidity varying means and a controller coo crating therewith for maintaining any esired condition of humidity within the apparatus, of control means movable in response to the lossin weight of a representative sample of the material being dried as the drying operation progresses, an electromagnetic device arranged to be actuated by said control means, and means operated by said elect'romagneticdevice for adjusting said controller to maintain predetermined different conditions of humidity within the drying apparatus as the drying operation progresses,

22. In an apparatus for drying materials which require diiferent conditions of temperature and humidity during the drying operation, temperature and humidity controllers having temperature-setting means cooperating with means for maintaining determined conditions of temperature within the apparatus and humidity-setting means cooperating with means for maintaining determined conditions of humidity within the" apparatus, an electromagnetic device, means actuated by said electromagnetic'device 'for adjusting said'temperature-setting means and said humidity-settin means, means for producing an action in cative of the loss of weight of a representative sam- Y ple of the material being dried as the drymg operation progresses, and means for means for pro ucin tueaeve sponse to said action.

23. In an apparatus for drying materials which 'l'BqllllG diiferent conditions of temperature and humidity during the drying operation, temperature and humiditycontrollers having temperature-setting means cooperating with means for maintaining determined conditions of temperature within the apparatus and humidity-setting means cooperating with means for maintaining determined conditions of humidit within the apparatus, an electromagnetic evice, a'temperature-adjusting means operatively connected with said temperature-setting means, a humidity-adjusting means operatively connected with said humidity-setting means, said temperature-adjusting means and said humidity-adjusting cam being moved by said electromagnetic device, means for producing an action indicative of the loss of weight of a representative sample of the material being dried as the drying operation progresses, and means for actuating said electromagnetic device in response to said action.

24. In an apparatus for drying materials which require diil'erent conditions of temperature during the drying operation, a

temperature controller having temperaturesetting means cooperating with means for maintaining determined conditions of temperature within the-apparatus, an electromagnetic devioe, means actuated by said electromagnetic device for adjusting the temperature-setting means, means for producing an action indicative of the loss of weight of a representative sample of the material being dried as the drying operation progresses, and means for causing said action to energize and actuate said electromagnetic device. v

25. In an apparatus for drying materials which require different conditions of temperature during the drying operation, a temperature controller having temperaturesetzting means. cooperating with means for maintaining determined conditions of temperature within the apparatus, an electromagnetic device, a temperature-adjusting cam operatively associated with the temperature-setting means, said temperatureadjusting ..means being moved a predetermined amount in one direction each time said electrom netic device is energized, an action indicative of the loss of w-eig t of a re rese-ntative sample of the material being drying operation progresses, and means for causing said action to energize said electromagnetic device.

26. In an apparatus for drying materials which requirediiferent conditions of humidity during the drying operation, a humidity ried as the loss of weight of a representative sam le of the material being dried as the rying operation progresses, and means for causing said action to energize and actuate said electromagnetic device.

27. In an apparatus for dryln materials which require different con itions of humidity during the drying operation, a humidity controller having humidity-setting means cooperating with means for maintaining determined conditions of humidity within the apparatus, an electromagnetic device, a humidity-adjusting means operatlvely associated with the humidity-setting means, said humidity-adjusting means being moved a predetermined amount each time said electromagnetic device is energized, means for producin an action indicative of the loss of weight 0 a representative sample of the material being dried as the drying operation progresses, and means for causing sald action to energize said electromagnetic device.

28. The combination in a drying apparatus having temperature var ing means and humidity varying means an controllers cooperating therewith for maintaining any desired conditions of temperature and humidity within the apparatus, of control means movable in response to the loss in weight of a representative sample of the material being dried as the drying operation progresses, "in electric motor arranged to be periodically operated by the action of said control means, and means operated by said motor for adjusting said controllers to main tain predetermined difl'erent conditions of temperature and humidity within the drylng apparatus as the drying operation pro+ grosses. v

29. The combination in a drying apparatus having temperature varying means and a controller cooperating therewlth for maintaining any desired condition of temperature within the apparatus, of control means movable in response to the loss in weight of a representative sample of the material being dried as the drying operation progresses, an electric motor arranged to be periodically operated by the action of said control means, and means operated by said motor for adjusting said controller to maintain predetermined different conditions of temperature within the drying apparatus as the drying operation rogresses.

30. The com )ination in a drying apparatus having humidity varying means and a controller cooperating therewith for maintaining any desired condition of humidity within the apparatus, of control means movable in response to the loss in weight of a representative sample of the material being dried as the drying operation progresses, an electric motor arranged to be periodically operated by the action of said control means, and means operated by said motor for adjusting said controller to maintain redetermined different conditions of humi it T within the drying apparatus as the drying operation progresses.

31. The combination in a drying apparatus having temperature varyin means and a controller cooperating therewith for maintaining any desired condition of tempera ture within the apparatus, of control means movable in response to the loss in weight of a representative sample of the material being dried as the drying operation progresses, and means actuated by said control means for adjusting said controller to progressively establish and maintain predetermined different conditions of temperature within the drying apparatus as the drying operation progresses.

32. The combination in a drying apparatus having humidity varying means and a controller cooperating therewith for maintaining any desired condition of humidity within the apparatus, of control means movable in response to the loss in weight of a representative sample of the material being dried as the drying operation progresses, and means actuated by said control means for adjusting said controller to progressively establish and maintain predetermined different conditions of humidity within the drying apparatus as the drying operation progresses.

The combination in a-drying apparatus having temperature varying means and humidity varying means and controllers cooperating therewith for maintaining any desired conditions of temperature and humidity within the apparatus, of control means movable in response to the loss in weight of a representative sample of the material being dried as the drying operation progresses, and means actuated by said control means for adjusting said controllers to progressively establish and maintain predetermined different conditions of temperature and humidity within the drying apparatus as the drying operation progresses.

34. The combination in a drying apparatus having temperature Varying means and humidity varying means and a controller cooperating therewith for maintaining any desired conditions of temperature and humidity within the apparatus, of controlling instrumentalities adapted to be adjusted so as to establish and maintain difl'erent conditions oftemperature and humidity within the apparatus, movable means operatively said control means and operatively connected to said movable means for adjusting said controlling instrunientalities to progressively establish and maintain the different conditions of temperature and humidity within the drying apparatus required in'the course of the drying operation.

35. The combination in a drying apparatus having temperature varying means and humidity varying means and a controller cooperating therewith for. maintaining any desired conditions of temperature and humidity within the apparatus, of controlling instrumentalities adapted to be adjusted so as to establish and maintain different conditions of temperature and humidity within the apparatus, control means responsive to the loss in weigh of a representative sample of the material eing dried, said control means including 388F195 of spaced electric contacts and a cooperating movable contact member operatively connected to a balancing device and arranged to progcssivcly engage said spaced contacts in consequence of the loss in weight of said representative sample as the drying operation progresses, and electromagnetic means actuated by the engagen'ient of said movable contact member with said spaced contacts for adjusting said controlling instrumentalities to progressively establish and maintain the different conditions of temperature and humiditv within the drying apparatus required in the course of the drymg operation.

36. The combination in a drying apparatus having temperaturevarying means and humidity varying means and acontroller cooperating therew th for maintaining any desired conditions of temperature and humidity within the apparatus, of controlling instrumentalities adapted to be adjusted so as to establish and maintain difl'crent conditions of temperature and humidity within the apparatus, movable means operatively associated with sa d instrumentalities and adapted when appropriately moved to adjust said instrumentalities to establish and maintain predetermined different conditions of temperature and humidity within the apparatus, control means responsive to the loss in weight of a representative sample of the material being dried, said control means including a series of spaced electric contacts and a cooperating movable contact member operatively connected to a balancing device and arranged to progressively engage said spaced contacts in consequence of the loss in weight of said representative sample as lhc drying operation progresses, and electromagnetic means actuated by the engagement of said movable contact member with said spaced contacts and operatively connected to said movable means for ad]usting said controlling instrumentalities to progressively establish and mamtainthe difierent con- \litions of temperature and humidity within the drying apparatus required in the course Jf' the drying operadon.

37. The combination in a drying apparatus having temperature varying means and humidity varying means and a controller cooperating therewith for-maintaining any desired conditions of temperature and humidity within the apparatus, of controlling mstrumentalities adapted to be adjusted so as to establish and maintain different conditions of temperature and'humidity within the apparatus, control means responsive to .the loss in weight of a re resentative sample -of the material being ried, said control means including two series of alternately arranged spaced electric contacts and a cooperating movable contact member operatively connected to a balancing device and arranged to progressively engage said spaced contacts in consequence of the loss in weight of said representative sample asthe drying operation progresses, each of said series of spaced electric contacts being included in a different electric circuit, an electromagnetic device arranged to be included in each of said circuits, means whereby said circuits are alternatel completed and said electromagnetic device energized andoperated by the progressive engagement of said movable Contact membenwi h said spaced contacts, and means whereby the operation of said electromagneticdevice adjusts said controlling instrumentali'ties to progressively establish and maintain the different conditions of temperature anl humidity within the drymg apparatus required in the course of the drying operation.

.38.=The combination in a drying apparatus having temperature varying means and humidity varying means and a controller cooperating therewith for maintaining any desired conditions of temperature and humiditywithin the apparatus, of controlling instrumentalities adapted to be adjusted so as to establish and maintain ditferent conditions of temperature and humidity within the apparatus, movable means operatively associated with said instrumentalities and adapted when appropriately moved to adjust said instrumentalities to establish and maintain predetermined different conditions of temperature and humidity within the apparatus, control means rcsponsive to the loss in weight of a representative sample of the material being dried, said control means including two series of alternately arranged spaced electric contacts and a coo crating movable contact member operative y connected to a balancing device and arranged to progressively engage said spaced contacts in consequence of the loss in weight of said representative sample as the drying operation progresses, each of said series of spaced electric contacts being included in a difierent electric circuit, an electromagnetic device arranged to be included in each of said circuits, means whereby said circuits are alternately completed and said electromagnetic device energized and operated by the progressive engagement of said movable contact member with said spaced contact, and means whereby the operation of said electromagnetic device adjusts said controlling in strumentalities to progressively establish and maintain the different conditionsfof temperature and humidity within the drying apparatus required in the course of the dryin operation.

39. The combination in a drying apparatus 'having temperature varyin means and humidity varying means an a controller cooperating therewith for maintaim ing any desired conditions of temperature and humidity within the apparatus, of control means movable in response to the loss in weight of a re resentative sample of the material being dried as the drying operation progresses, said controlmeans includin a series of spaced electrical" contacts an a cooperating movable contact member, an electric motor, meanswhereby said electric motor is energized and rotated a predetermined number of revolutions each time said movable contact member engages one of said spaced contacts, and means operated by said motor for adjusting said controller to maintain predetermined different conditions of temperature and humidity within the drying apparatus as the drying operation progresses. i

40. The combination in a dryingapparatus having temperature varyin means and humidity varying means an a controller cooperating therewith fpr maintaining any desired conditions of temperature and humidity within the apparatus, of control means movable in response to the loss in weight of a representative sample of the material being dried as the drying operation progresses, said control means including a series of spaced electrical contacts and a cooperating movable contact member, an electric motor, means whereby said electric motor is energized and rotated a predetermined number of revolutions each time said movable contact member enga es one of said spaced contacts, a rotatable e ement operatively connected to said motor and arranged to be uniformly turned each time said motor is energized; a tem erat ure-adjusting means and a. humidity-a Justmg cam operat vely associated with said rotatable element, and

means 0 erated by said means for adjusting sai controller to maintai predetermined different conditions of and humidity within th dryi apparatus as the drying o ration Ms.

control means movable in response to the loss in weight of a representative sample of the material being dried as the dryin 0 eration progresses, said control means inc uding two series of alternately arranged'spaced electrical contacts and a cooperating movable contact member arranged to engage said contacts in sequence, each of said series of spaced electrical contacts being included in a different electric circuit, an electric motor means adapted to alternately include said electric motor in one and then the other of said electric circuits after each of a predetermined number of revolutions of the motor, said electric circuits being alternately completed and said electric motor energized and rotated said predetermined number of revolutions each time said movable contact member engages one of said spaced electrical contacts, and means operated by said motor for adjusting said controller to maintain predetermined difi'erent conditions of temperature and humidity within the drying apparatus as the drying operation' progresses.

42. The combination in a drying apparatus having temperature'varying means and a controller cooperating therewith for main taining any desired conditions of temperature within the apparatus, of controlling instrumentalities adapted to be adjusted so as to establish and maintain different condi-' tions of temperature within the apparatus, movable means operatively associated with said instrumentalities and adapted when appropriately moved to adjust said instrumentalities to establish and maintain predetermined difi'erent conditions of temperature within the apparatus, control means responsive to the loss in weight of a representative sample of the material being dried, and means actuated by said control means and operatively connected to said movable means for adjusting said controlling instrumentalities to progressively establish and maintain the different conditions of temperature withinthe drying apparatus required in the course, of the drying oper-. ation.

43. The combination in a drying appa ratus having temperature varying means and a controller cooperating therewith for any desired conditions of tememperature perature within the apparatus, of controlling instrumentalities adapted to be adjusted so as toestablish and maintain difierent conditions of temperature within the apparatus, control means responsive to the loss in weight of a representative sample of the material being dried, said control means including a series of spaced electric contacts and a cooperating movable contact member operatively connected to a balancing device and arranged to progressively engage said spaced contacts in consequence of the loss in weight of said representative sample as the drying operation progresses, and electromagnetic means actuated by the engagement of said movable contact member with said spaced contactsfor adjusting said controlling instrumentalities to progressively establish and maintain the different conditions of temperature within the drying apparatus required in the course of the drying operation.

4-1;. The combination in a drying apparatus having temperature varying means and a controller cooperating therewith for maintaining any desired conditions of temperature within the apparatus, of controlling instrumentalities adapted to be ad usted so as to establish and maintain different conditions of temperature within the apparatus, movable means operatively associated with said instrumentalities and ada ted when appropriately moved to adjust sai instrumentalities to establish and maintain predetermined different conditions of temperature within the apparatus, control means responsive to the loss in weight of a representative sample of the material being dried, said control means including a series of spaced electric contacts and a cooperating movable contact member operatively con-' nected to a balancing device and arranged to progressively engage said spaced contacts in consequente of the loss in weight of sai representative sample as the drying operatlon progresses, and electromagnetic means actuated by the engagement of said movable contact member with said spaced contacts and operatively connected to said movable means for adjusting said controllin instrumentalities to progressively estab ish and maintain the different conditions of temperature within the drying apparatus required in the course of the drying operation.

-15. The combination in a drying apparatus having temperature varying means and a controllercooperating therewith for maintaining any desired conditions of temperature within the apparatus, of controlzling instrumentalities adapted to be adjusted so as to establish and maintain difi'erent conditions of temperature within the apparatus, control means responsive to the loss in weight of a representative sampleof the material being dried, said control means including two series of alternately arranged spaced electric contacts and a cooperating movable contact member operatively connectedto a balancing device and arranged to progressively engage said spaced contacts in consequence of the loss in Weight of said representative sample as the drying operation progresses, each of said series of spaced electric contacts being included in a different electric circuit, an electromagnetic device arranged to be included in each of said circuits, means whereby said circuits are alternately completed and said electromagnetic device energized and operated by the progressive engagement of said movable contact member with said spaced contacts, and means whereby the operation of said electromagnetic device adjusts said controlling instrumentalities to progressively establish and maintain the different conditions of temperature within the drying apparatus required in the course of the drying operation.

46. The combination in a drying apparatus having temperature varying means and a controller cooperating therewith for maintaining any desired conditions of temperature within the apparatus. of control ling instrumentalities adapted to be adjusted so as to establish and maintain difl'erent conditions of temperature within the apparatus, movable means operatively associated with said instrumentalities and adapted when appropriately moved to adjust said instrumentalities to establish and maintain predetermined difierent conditions of temperature within the apparatus, control means responsive to the loss in weight of a representative sample of the material being dried. said control means including. two series of alternately arranged spaced electric contacts and a cooperating movable contact member operatively connected to a balancing device and"arranged to progressively engage said spaced contacts in consequence of the loss in weight of said representative sample as the drying operation progresses, each of said series of spaced electric contacts being included in a difi'erent electric circuit. an elec- 'tromagnetie device arranged to be included in each of said circuits, means whereby said circuits are alternately completed and said electro-ma netic device energized and operated by t 1e progressive engagement of said movable contact member with said spaced contact, and means whereby the operation of said electromagnetic device adjusts said con trolling instrumentalities to .rogressively establish and maintain the di erent conditionsof temperature within the drying apparatus required in the course of the drying operation.

47. The combination in a drying apparatus having temperature varying means and a controller cooperating therewith for maintaining any desired conditions of temnasaa'ra perature Within the apparatus, of control means movable in response to the loss in weight ofa representative sample of the material being dried asthe drying operationprogresses said control means including a series of spaced electrical contacts and a cooperating movablecontact member, an electric motor, means whereby said electric motor is energized and rotated a predetermined number of' revolutions each time said movable contact member engages one of said spaced contacts, and means operated by said motor for adjusting saidcontroller to maintain predetermined different conditions of. temperature Within the drying apparatus as the drying operation progresses.

4,8. The combination in a drying apparatus having temperature varying means and a controller cooperating therewith for maintaining any desired onditions of temperature within the app-ratus, of control means movable in response to the loss in weight of a representative sample of the material being dried as the drying operation progresses, said control means including a series of spaced electrical contacts and a cooperating movable contact member, an electric motor, means whereby said electric motor is energized ahdmotated a predetermined number of revolutions each time said movable contfact member engages one of said spaced contacts, a rotatable element operatively connected to' said motor and ;arranged to be uniformly turned each time said motor is energized, atemperatureadjusting means 'operatively associated with said rotatable element, and means operated by said means for adjusting said controller to maintain predetermined different conditions of temperature within the drying apparatus as the drying operation progresses.-

49; The combination in a drying apparatus having temperature varying means and a controller cooperating therewith for main-p taining any desired conditions of temperature Within the apparatus, of control means movable in response to the loss in weight of a representative sample of the material be ing dried as the drying operation progresses, said control meansincluding two, series of alternately arranged spaced electrical contacts and a cooperating movable contact member arranged to engage said contacts in sequence, each of said series of spaced electrical contacts being included in a different electric circuit, an electric motor, means adapted to alternately include said electric motor in one and then the other ofsaid electric. circuits after each of a predetertacts, and means operated by said motor for adjusting said controller toniaintain predetermined d'iflerent conditions of temperature within the drying apparatus as the dry ing operation progresses.

- 50. The combination in a drying apparatus having humidity varying means and a controller cooperating therewith for maintaining any 'desized conditions of humidity Within the apparatus. of controlling instrumentalities adapted to be adjusted so as to establish and maintain diiierent conditions of humidity within the apparatus, movable means operativcly associated with said instrumentalities andadapted when ap'propii ately moved to adj List said instrumentalities to establish and maintain predetermined different conditions of humidity Within the apparatus. control means responfive to the loss in Weight ofa representative sample of the material being dried, and means actuated by said control means and operatively connected to said movable means for adjusting said controlling instrumentalities to progressive- 1v establish and maintain the \diflerent conditions of humidity within the drying apparatus required in the course of the drying operation. a

51. The combination in a drying apparatus having humidity varying means and a controller cooperating therewith for maintaining any desired conditions of humidity Within the ap aratus, of controlling instrumentalities at apted to be adjusted so as to dried, said control means including a series of spaced electric contacts and a cooperating movable contact member operatively connected to a balancing device and arranged to progressively engage said spaced contacts in consequence of the loss in Weight of said representative sample as the drying operation progresses, and electromagnetic means actuated by the engagement of said movable contact member with said spaced contacts for adjusting said controlling instrumentalities dr in a .aratus re aired in the course of" the drying operation.

52. The combination in a drying apparatus having humidity varying means and a controller cooperating therewith for maintaining any desired conditions of humidity within the apparatus, of controlling instrumentalities adapted to be adj usted'so as to establish and maintain different conditions of humidity within the apparatus, movable means operatively acsociatedwith saidinstrumentalities and adapted when approprh,

ately moved to adjust said instrumentali-' ities to establish and maintain predetertact member operatively connected to a balancing device and arranged toprogressive- 1y engage said spaced contacts in consequence of the loss in weight of said representative sample as the drying operation progresses, and electromagnetic means actuated by the engagement of said movable contact member with said spaced contacts and operatively connected to said movable means for adjusting said controlling mentalities to progressively estab ish and maintain the ditt'erent conditions of humidity within the drying apparatus required in the course of the drying operation.

The combination in a drying apparatus having humidity varying means and a controller cooperating therewith for main taining any desired conditions of humidity within the apparatus, of controlling instrumentalities adapted to be adjusted so as to establish and maintain different conditions of humidity within the apparatus, control means responsive to the loss in weight of a representative sample of the material being dried, said control means including two series of alternately arranged spaced electric contacts and a cooperating movable contact member operatively connected to a balancing device and arranged to progressively engage said spaced contacts in consequence of the loss in weight of said representative sample as-the drying operation progresses, each of said series of s aced electric contacts being included in a di erent electric circuit, an electromagnetic device arranged to be ineluded ineach of said circuits, means whereby said circuits are alternately completed and said electromagnetic device energized and operated by the progressive engagement of said movable contact member with said spaced contacts, and means whereby the o 'eration of said electromagnetic device a justs said controlling instrumentalities to rogressively establish and maintain the difcrcnt conditions of humidity within the drying apparatus required in the course of the drying operation. 4

54. lh combination in a dryingapparatus having humidity varying means and a controller cooperating therewith for maintaining any desired conditions of humidity within the apparatus, of controlling instrumentalities adapted to be adjusted so as to establish and maintain difi'erent conditions of humidity within the apparatus, movable means operatively associated with said instrumentalities and adapted when appropriately moved toadjust said instrumentalities to establish and maintain predetermined instrudifferent conditions of humidity within the apparatus, control means responsive to the loss in weight of a representative sample of the material being dried, said control means including two series of alternately arranged spaced electric contacts and a cooperating movable contact member operatively connected to a balancing device and arranged to progressively engage said spaced contacts in consequence of the loss in weight of said representative sample as the drying operation progresses,each of said series of s aced electric contacts being included in a di erent electric circuit, an electromagnetic device arranged to be included in each of said circuits, means whereby said circuits are alternately completed and said electromagnetic device energized and operated by the progressive engagement of said movable contact member with said spaced contact, and

means whereby the operation of said electromagnetic device adjusts said controlling instrumentalities to rogressively establish and maintain the ifi'erent conditions of humidity within the drying apparatus required in the course of the drying operation.

5-5. The combination in a drying apparatus having humidity varying means and a controller cooperating therewith for maintaining any desired conditions of humidity within the apparatus, of control means movable in response to the loss in weight of a representative sample of the material being dried as the drying operation progresses said control means including a series or spaced electrical contacts and a cooperating movable contact member, an electric motor, means whereby said electric motor is energized and rotated a predetermined number of revolutions each t1me said movable contact member engages one of said spaced contacts, and means operated by said motor for adjusting said controller to maintain predetermined different conditions of humidity within the drying apparatus as the drying operation progresses.

56. The combination in a drying apparatus having humidity varying means and a controller cooperating therewith for maintaining any desired conditions of humidity within the apparatus, of control means movable in response to the loss in weight of a representative 'sample ot' the material being dried as the drying operation progresses, said control means including a series of spaced-electrical contacts and a cooperating movable contact member, an electric motor, means whereby said electric motor is energized and rotated a predetermined number of revolutions each time said movable contact member en ages one of said spaced contacts, a rotata le element operatively connected to said motor and arranged to be uniformly turned each time said motor is energized, a humidity-adjusting means operatively associated with said rotatable element, and means operated by said means for adjusting said controller to maintain predetermined difierent conditions of humidity within the drying apparatus as the drying operation progresses. A

57. The combination in a drying apparatus having humidity varying means and a controller cooperating therewith for maintaining any desired conditions of humidity within the apparatus, of control means movable in response to the loss in weight of a representative sample of the material being dried as the drying operation progresses, said control means including two series of alternately arranged spaced electrical contacts and a cooperating movable contact member arranged to engage said contacts in sequence, each of said series of spaced electrical contacts being included in a diiferent electric circuit, an electric motor, means adapted to alternately include said electric motor Mom and then in the other of said electric circuits after each of a predetermined number of revolutions of the motor, said electric circuits being alternately completed and said electric motor energized and rotated said predetermined number of revolutions each time said movable contact member engages one of said spaced electrical contacts, and means operated by said motor for adjusting said controller to maintain predetermined different conditions of hu- .midity Within the drying apparatus as the drying operation progresses.

In testimony whereof I aflix my signature.

JOHN BERCHMANS WELCH.

said control means including two series of alternately arranged spaced electrical contacts and a cooperating movable contact member arranged to engage said contacts in sequence, each of said series of spaced electrical contacts being included in a difl'erent electric circuit, an electric motor, means adapted to alternately include said electric motor in one and then in the other of said electric circuits after each of a predetermined number of revolutions of the motor, said electric circuits being alternately completed and said electric motor energized and rotated said predetermined number of revolutions each time said movable contact member engages one of said spaced electrical contacts, and means operated by said motor for adjusting said controller to maintain predetermined difl'erent conditions of humidity Within the drying apparatus as the drying operation progresses.

In testimony whereof I afiix my signature.

JOHN BEROHMANS WELCH.

Certificate of Correction. It ishereby certified that in Letters Patent No. 1,583,376, granted May 4, 1926,

upon the application of John Berchmans \Velch, improvement in Apparatus for Drying and the Like,

specification requiring correction as out the word of New Orleans, Louisiana, for an errors appear in the printed follows: Page 2, line 11, for the word woods read wood; page 5, line 93, for the word start be, first occurrence; page 7, line 105, clalm read star; page 6, line 60-, strike 6, for the misspelled word represenative read representative,- page 10, line 115, claim 25, for the word cam read men/n8; page 16, line 6, claim 52, for the word cooperative and that the said Letters Patent should be read with these corrections conform to the record of the case in the Patent Ofiice.

cooperating therein that the same may read Signed and. sealed this th day of July, A. D. 1926.

M. J. MOORE, Acting Commssimer of Patents. 

